Merino and wool garments

Posted byJohn10/05/20190 Comment(s)

There are a couple of ways to assess the quality of a wool garment… first is its micron.

The micron count is an indication of the thickness of the wool fibre. Ordinary wool is about 40 microns, reasonably thick in the scheme of things and as a result can get a bit itchy. Merino wool starts at around 26 microns and can go as low as 15 depending on just how much of a “merino” the sheep is. I say this because all merino sheep are crossed with other breeds (i.e. hardy desert sheep don’t do too well in cold, muddy NZ – they get footrot etc, so they’re made more hardy by crossing them with other sheep). Obviously, you don’t want the micron to be too fine either – you need to be able to wear it without it breaking down.

According to NZ Merino (who supply Icebreaker and Smartwool) the sweet spot is somewhere between 21 and 25. The finer thread makes it more comfortable and less itchy. Where it’s grown has NO IMPACT on the micron count.

The second factor in the quality of a merino fibre is staple length – this is the length of the wool when it’s cut from the sheep. Typically, growers want to achieve staples of around 3 to 4 inches because when loomed, this creates a really strong fibre. Too short, and the fibres can break down, get spiky and itchy on the skin. It does vary season on season – colder conditions will create longer staples, warmer conditions shorter staples. As a side note, variable conditions will create inconsistent staples… which is why New Zealand merino is so highly sought after.

Due to the mountainous terrain, farmers can move their flocks to higher and lower altitudes to help avoid these climatic variations –the link between a merino garment and nature runs super deep. Where it’s grown does have a big impact on the end quality of the wool itself, but that’s not to say this level of quality can’t be achieved outside of New Zealand, and Australia, South Africa and Uruguay are also known to produce high quality fibres. Additionally, it should be said that while Smartwool and Icebreaker can trace much of their materials back to NZ, their supplier (NZ Merino) does source wool for them outside of NZ – especially from the countries previously mentioned.

And just a bit more on Merino….

People buy it because of its thermo dynamic properties; it’s cool when your warm, warm when you’re cool (my line is that it works on a sheep)…

Its Hydrophilic (as opposed to Hydrophobic) – it moves moisture by absorbing it, but will absorb moisture in its Vapour State. A polypro (any polypro or other synthetic base layer) can only move moisture in its liquid state (which is sweat). Given Gore Tex will only allow water vapour to pass through (say) a jacket or a pair of shoes – you can see how a merino layer can assist other technical garments – as opposed to inhibit them.

It’s moisture eating… well not really. The fibres themselves are a little bit like swiss cheese; they trap oils, skin particles, minerals and other nasties inside the fibre but don’t allow the odour to escape – think of the way bi-carb soda works. These nasties will also sit inside a synthetic layer, but will give off odour. You can get merino to smell as the fibres can only carry so much, but it takes heaps longer than with a synthetic. You can fix this by washing it.

Merino biodegrades, Synthetic does not.

Merino is (increasingly) more expensive, and it’s not to say you can’t get good synthetic baselayers. It’s becoming increasingly common to have blends – even top end brands like Patagonia and Arc’teryx are doing it. As another side note – Bridgedale are one of the best in the business at this.

When people say they’re allergic to wool – they’re normally allergic to lanolin, the oils in the wool when its cut from the sheep. This is typically removed from merino before its loomed.

Why technical base layer fabrics dry quickly and cool you down …

Woolen base layers are designed to be worn next to the skin, providing user comfort by maintaining body temperature and controlling moisture. They are highly wicking (will spread moisture out over a large area), fast drying and breathable. It is therefore essential to maintain these properties when caring for woolen base layers.

Base layers need to be cared for properly to keep them in top condition…

Base layers are fantastic for regulating your temperature and controlling body moisture, but to keep them functioning properly care must be taken when washing.

It is recommended to wash woolen items in mild liquid detergents and to avoid using powder or bio detergents, which contain enzymes. Using conventional household detergents or fabric softeners can impair wicking properties by causing the fabric to retain moisture. This leads to reduced wicking capabilities and slow drying of the fabric, resulting in reduced user comfort. Additionally, standard household softeners can lead to pilling over a number of washes.

Anyone who is active outdoors will benefit from wearing a base layer…

All active people should use base layers to effectively manage body moisture and regulate temperature. Hill walkers, runners, cyclists, and mountaineers are among those who utilize base layers to maintain their comfort whilst active.

Wash your base layers after use…

Once your base layer has been used a few times wash it with Nikwax Wool Wash™ to refresh, remove odours, soften and enhance drying and cooling. Always apply Nikwax Wool Wash™ to used woollen base layers, socks and travel clothing to keep them in perfect condition.

Using conventional household detergents and fabric softeners will impair the wicking properties of base layer fabrics. Standard household detergents do not stop odors from building up in the fabric when in use. Conventional fabric softeners leave water-hating (hydrophobic) residues that will reduce the performance of the fabric, preventing it from spreading moisture and working to its maximum potential.